Heating combustion chamber, glow plug increases fuel ignitibility and makes fuel in the foggy state easily when engine is cold. Thus, glow plug makes engine starting easily and decreases exhaust gas produced just after turning engine on when engine is cold.
ECM controls operation and operating duration of glow plug relay which supplies power to glow plug with ECTS signal, battery voltage and IG KEY ON signal.
Through glow lamp in cluster, ECM let drivers know if glow plug is ON.
P0381 is set when 1)excessive voltage is detected or 2)no current is detected like open or short to ground in glow lamp control circuit for more than 1 sec. at glow lamp ON condition. This code is due to open in glow lamp control circuit or internal open in filament of glow lamp component.
Item
Detecting Condition
Possible Cause
DTC Strategy
Voltage monitoring
Open in glow lamp
Glow lamp circuit
Enable Conditions
IG KEY "ON" (monitoring only performed within lamp operating condition)
Threshold Value
Short to battery
Short to GND, Wiring open
Diagnostic Time
1.0 sec.
Fail Safe
Fuel cut
NO
EGR Off
Fuel Limit
MIL